Happy 70th birthday to the UFO phenomenon. Kenneth Arnold's 24 June 1947 sighting of nine strange UFOs over the Cascade Mountains in Washington State gave rise to the term "flying saucer". While people have seen strange things in the sky throughout human history, Arnold's sighting marked the genesis of the modern UFO mystery. 70 years on, the mystery remains unsolved, despite some die-hard debunkers claiming that the phenomenon is dead, and despite some true believers stating that the extraterrestrial hypothesis is proven. Neither group are correct. The UFO phenomenon remains unsolved, and perhaps unsolvable (and I say this as someone who had responsibility for the subject for the British government). It can be occasionally frustrating, sometimes fun, and always intriguing. So, once again, happy 70th birthday to UFOs! credit Nick Pope